Also, OP, keep in mind aluminum isn't like steel which often can be bent back into shape without significant damage to the structural integrity of the metal; bend it once even a bit (except for really thin pieces), and you've lost most of your strength. It's also not really all that rigid/springy like steel - it doesn't "bounce back" nearly as well. In short, use it either for makeshift projectile weapons or for show, but practical use in melee is basically completely out of the question.
It is, however, very easy to work with and is much lighter than steel, so it does have its pluses.
As for lead, be careful - it is more harmful to your health when working with it. It is also very heavy and soft, so it's not practical for basically any form of weaponry except maybe old-fashioned replicas and such.
